Abstract [en]

Large conspicuous eyespots have evolved in multiple taxa and presumably function to thwart predator attacks. Traditionally,large eyespots were thought to discourage predator attacks because they mimicked eyes of the predators’ own predators.However, this idea is controversial and the intimidating properties of eyespots have recently been suggested to simply be a consequenceof their conspicuousness. Some lepidopteran species include large eyespots in their antipredation repertoire. In thepeacock butterfly, Inachis io, eyespots are typically hidden during rest and suddenly exposed by the butterfly when disturbed.Previous experiments have shown that small wild passerines are intimidated by this display. Here, we test whether eyespots alsointimidate a considerably larger bird, domestic fowl, Gallus gallus domesticus, by staging interactions between birds and peacockbutterflies that were sham-painted or had their eyespots painted over. Our results show that birds typically fled when peacockbutterflies performed their display regardless of whether eyespots were visible or painted over. However, birds confronting butterflieswith visible eyespots delayed their return to the butterfly, were more vigilant, and more likely to utter alarm calls associatedwith detection of ground-based predators, compared with birds confronting butterflies with eyespots painted over. Becauseproduction of alarm calls and increased vigilance are antipredation behaviors in the fowl, their reaction suggests that eyespotsmay elicit fear rather than just an aversion to conspicuous patterns. Our results, therefore, suggest that predators perceive largelepidopteran eyespots as belonging to the eyes of a potential predator. Key words: chicken, predator–prey interactions, startledisplay.